Planning of the 3700-4200 MHz band - consultation 27/2019

After considering the issues and suggestions raised in submissions, we consulted on planning options for the 3700–4200 MHz band.

In Australia, the 3700–4200 MHz band is currently used by a mixture of services and applications including point-to-point links, coordinated fixed satellite service (FSS) earth stations, radiodetermination and various low power class licensed devices.

Internationally, there has been growing interest in investigating options to make all or part of the 3700–4200 MHz band available for use by wireless broadband (WBB) services including 5G. These investigations have all carefully considered legacy uses of the band, especially by the FSS for ‘C-band’ satellite services that offer a range of unique characteristics important to the satellite operators and users.

Several countries have allocated or are in the process of examining options for the use of all or part of the 3700–4200 MHz band for WBB services. Most, including European and Middle Eastern countries, are focusing on the 3400–3800 MHz frequency range for initial 5G deployments. However, Japan recently awarded spectrum in the 3600–4100 MHz band and United Kingdom announced arrangements for shared access in the 3800–4200 MHz band. Canada and the United States of America are also looking at options to make all or part of the band available for WBB. This includes options for shared access with incumbent services.

In Australia, these international developments have increased interest from several competing services, including incumbent and WBB services, for access to the band. In contrast, elements of the satellite community have clearly articulated their concerns about any possible changes that would impact C-band satellite services.

The ACMA is alert to the needs of existing FSS and point-to-point uses of the band, as well as the potential for both wide-area and site-based (for example, Fixed Wireless Access or FWA) wireless broadband.

In response to these international and domestic developments, the 3700–4200 MHz band has been moved to the initial investigation stage of the ACMA’s work program for major band replanning activities, as outlined in the Draft five-year spectrum outlook 2019–23 (draft FYSO). Considering the whole band will simultaneously maximise the opportunity for a balanced approach that takes appropriate account of all interests. It is intended that undertaking a review of the band and affirming or otherwise changing domestic planning arrangements will provide increased certainty for all parties.

This paper identifies current uses and interests in the band—domestically, as well as emerging international trends. It seeks evidence on a range of issues to better understand the future needs of incumbent and prospective new services in the band. The aim is to identify what, if any, changes to arrangements in the band should be considered to ensure its use maximises the overall public benefit into the future.

To aid discussion, a number of possible planning scenarios for the band are presented:

• Provide access to the entire band for new services on either an exclusive or shared basis.
• Provide access to one or more segments of the band for new services on either an exclusive or shared basis. Maintain existing arrangements for incumbent services in the rest of the band.
• Provide access to one segment of the band on an exclusive basis to new services. Provide access for new services to another segment of the band on a shared basis. Maintain existing arrangements for incumbent services in the rest of the band.
• Maintain existing arrangements.

While the ACMA has yet to form any views on preferred long-term arrangements, these scenarios provide a means for examination of the follow issues:

• What services/applications should be accommodated in the band?
• Which frequencies ranges should be made available for these services/applications?
• Which geographic areas should be made available for these services/applications?
• On what basis should access be provided? Should access be granted on an exclusive or shared basis, on a coordinated or uncoordinated basis?
• What licensing mechanisms are appropriate?

The paper also examines compatibility issues with adjacent band services, as well as the potential benefits of aligning arrangements in all or part of the 3700–4200 MHz band with the lower adjacent 3.6 GHz band.

It is important to note that while this paper includes substantial discussion on possible wireless broadband use of the band, this does not indicate a predisposition on behalf of the ACMA regarding possible changes to the band. Rather, it reflects the current international and national focus of WBB as one of a number of possible uses of the band. The ACMA therefore considers it important to gain as much information as possible on this potential use of the band as an addition to further information on existing supported uses.

Submissions in response to this discussion paper will help the ACMA assess whether there is a case for further consideration of arrangements in the 3700–4200 MHz band, including whether or not to progress the band to the preliminary replanning stage of the ACMA replanning process. If progressed, there will be an additional public consultation that will canvas detailed planning options for the band before any regulatory decisions are made.

1. Are there any other international developments in the 3700–4200 MHz band that the ACMA should be aware of?
2. What are the future requirements of point-to-point links and FSS earth stations in the 3700–4200 MHz band? Does this differ by geographical area and/or segment of the band?
3. If licensed point-to-point links and FSS earth stations are affected by replanning activities in the 3700–4200 MHz band, what alternative deployment options could be considered?
4. In the event arrangements are made for new services in the 3700–4200 MHz band, do stakeholders have any comments on the ACMA’s proposal to maintain the existing arrangements for Radiodetermination and LIPD devices, and the existing policy around TVRO systems?
5. What are the future requirements for WBB services in the 3700–4200 MHz band and what arrangements should be considered? Does this differ by geographical area and/or segment of the band?
6. What WBB deployment scenarios should be considered for the 3700–4200 MHz band? Should use be limited to one scenario or should more flexible arrangements be implemented?
7. What is the current and planned availability of fixed and mobile WBB equipment in the 3700–4200 MHz band?
8. Is there interest in the use of other new service types in the 3700–4200 MHz band?
9. What services/applications should be accommodated in the 3700–4200 MHz band?
10. Which frequencies ranges should be made available for these services/applications?
11. Which geographic areas should be made available for these services/applications?
12. On what basis should access be provided? Should access be granted on an exclusive or shared basis, on a coordinated or uncoordinated basis, et cetera?
13. What licensing mechanisms are appropriate (spectrum, apparatus or class licensing)?
14. If arrangements for WBB specifically are implemented in the 3700–4200 MHz band, are the proposed interference management techniques with services in the 3.6 GHz band suitable? Are any other techniques proposed? Are there any other compatibility issues with the 3.6 GHz band the ACMA should consider?
15. Should the ACMA consider extending existing apparatus and spectrum licence arrangements in the 3.6 GHz band into the 3700–3800 MHz band or another segment of the 3700–4200 MHz band?
16. Is there any additional information available that would assist the ACMA in assessing compatibly of potential new WBB services in the 3700–4200 MHz band with WAIC and radio altimeter systems in the 4200–4400 MHz band?